This invention relates generally to gas turbine engines and, more particularly, to a valve assembly for gas turbine engines.
At least some known aircraft gas turbine engines include a fan, a compressor, a combustor, a high pressure turbine, a low pressure turbine and an augmentor or “afterburner”. Airflow entering the fan is compressed. Airflow exiting the fan is split where a portion is directed into the compressor and the remaining portion, referred to as fan bypass flow, is directed into a bypass passage where it bypasses the compressor, the combustor, the high pressure turbine and the low pressure turbine. Airflow entering the compressor is compressed and directed to the combustor where it is mixed with fuel and ignited, producing hot combustion gases used to drive both the high pressure and the low pressure turbines. Moreover, at least some known gas turbine engines, combine, in the augmentor, a portion of the fan bypass flow with the airflow exiting the low pressure turbine. Furthermore, at least some gas turbine engines include a valve assembly that is configured to regulate at least a portion of the fan bypass air entering the augmentor. However, known valve assemblies include crank-arms that are driven by hydraulic actuators. Accordingly, such valve assemblies are relatively complex to design and add additional cost and additional weight to the aircraft thus reducing the fuel efficiency of the aircraft.